The 47-year-old actress apologized to the 40-year-old "The Voice" coach and his girlfriend, Gwen Stefani, after calling out Shelton on Twitter for his recent remarks on Republican presidential candidate Donald Trump.
"I regret commenting," the former "Will & Grace" star tweeted Thursday. "My passions got the better of me. Sorry. @gwenstefani @blakeshelton."
Messing had entreated Stefani to reason with Shelton after mistakenly assuming the country star was endorsing Trump in a new interview.
She voiced her incredulity at Shelton's remarks in a since-deleted tweet.
"Omg. How? @gwenstefani please talk to your man to not vote for the person who will STRIP you of your rights," she wrote.
Shelton thanked Messing for her apology and assured the actress, "I don't endorse anybody. For this very reason!"
The singer had appeared complimentary of Trump in the Aug. 6 issue of Billboard magazine.
"Whether you love him or hate him, he says what he thinks, and he has proven that you don't always have to be so afraid" he said of Trump. "A lot of people are pulling for him, no matter how much Hollywood fights it."
Messing is a supporter of Democratic presidential candidate Hillary Clinton and attended night two of the Democratic National Convention this week.
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